1. Field of the Invention
The present invention relates to novel compounds of substituted phenylcyclopropane carboxylic acid esters which have excellent insecticidal activity to various insects injurious to sanitation as well as agriculture, horticulture and forest. 2 Description of the Prior Arts
Recently, structure modifications of natural pyrethrin have been widely studied and various cyclopropane carboxylic acid ester derivatives have been used as insecticides.
The present invention is to provide novel insecticidal compounds having superior insecticidal activity to those of the conventional pyrethroids.
The inventors have studied on structural modifications of pyrethroids and have found that the novel substituted phenylcyclopropane carboxylic acid esters have strong insecticidal effect and wide insecticidal spectrum and are substantially non-toxic to fishes and shell-fishes.
Heretofore, certain phenylcyclopropane carboxylic acid derivatives have been known.
The compounds having the formula ##STR3## have been known in Collection of Czechoslovak Chemical Communication 24 2460 (1959) and 25 1815 (1960).
These compounds are carboxylic acid esters having ##STR4## as the alcohol moiety. However, insecticidal activity of the compounds for houseflies is only similar to that of allethrin of one of the commerciallized pyrethroids when the substituent on the phenyl group is a hydrogen atom and the insecticidal activity is inferior when the substituent on the phenyl group is chlorine, or fluorine atom or methyl or methoxy group.
The compounds having the formula ##STR5## has been disclosed in Bochu Kagaku Vol. 27, III, page 51. However, the insecticidal activity of the compound is only similar to that of allethrin.
The inventors have checked a phenylcyclopropane carboxylic acid ester illustrated below. ##STR6## This compound has no substituent on phenyl group. However, an insecticidal activity of this compound is quite low.
On the other hand, the substituted phenyl cyclopropane carboxylic acid esters of this invention possess high insecticidal effects as described later in this invention.
It is important to obtain an insecticidal compound having highly insecticidal effects and widely used for controlling insects injurious to sanitation as well as agriculture, horticulture and forest.